One Day in the Life of a Chinook

Map Courtesy of the University of
Illinois

As a result of a strong Chinook effect at noon
MST on
December 19, 2003, Cut Bank and Great Falls
recorded highs of 59 and 56 degrees
respectively. Valier, 20 miles south of Cut
Bank, reached 61 degrees. In contrast,
Kalispell and Missoula only reached 23 and
31. The temperature map above shows that a
large areas east of the Rocky Mountains
experienced Chinook winds on that day, as
evidenced by the warmer colors extending
from Canada to Colorado.

Below:
When you compare the topography map
below to the temperature map (above) you can
see a strong correlation between the Chinook
winds and the shape of the land. The warm
winds develop on the east slope of the
Rockies. In some places this area is called
the "Rocky Mountain Front".

Map courtesy
of NASA

Not exactly . . . Many believe that the word "Chinook" means "snow eater" . . . A strong Chinook can make a foot of snow all but vanish in a day as the snow partially melts, and partially evaporates (sublimates) in the dry wind. Others believe the true origin of the name is that "Chinook Wind" in the fur trade era meant that the wind was coming from the direction of the Chinook Indians (the lower Columbia River).